Feeder mechanism with adjustable pickup heads

ABSTRACT

In a sheet feeder apparatus, a feeder mechanism for picking up sheets from a stack of sheets of a material includes a support bar, at least one pickup head, and an adjuster. The support bar includes cylindrical ends and an intermediate portion between the cylindrical ends. The cylindrical ends are configured to pivotally couple to control arms of the sheet feeder apparatus. The pickup heads are coupled to the intermediate portion of the support bar and an adjuster is coupled to the support bar at one of the cylindrical ends. The adjuster includes a bracket coupled to the intermediate portion of the support bar, a pivot arm selectively pivotable about the cylindrical end of the support bar, and an adjustment mechanism coupled between the bracket and the pivot arm. The adjustment mechanism pivots the support bar relative to the pivot arm to thereby tilt the pickup heads.

TECHNICAL FIELD OF THE INVENTION

The present invention relates generally to a sheet feeder apparatus.More specifically, the present invention relates to a feeder mechanismfor a sheet feeder apparatus having adjustable pickup heads.

BACKGROUND OF THE INVENTION

A sheet feeder apparatus is a device that holds a stack of paper,cardstock, and the like, and feeds each sheet into a printer, printingpress, or similar device one sheet at a time. In a sheet feederapparatus, a feeder mechanism is typically implemented to lift a singlesheet of material from the top of a stack of sheets of like material.Suction cups are widely utilized in feeder mechanisms for picking up thesheets of material. Typically, the lip of the suction cup is driven intocontact with the surface of the sheet. Suction or a partial vacuuminside the suction cup causes ambient air pressure to force the cupagainst the contact surface and so hold it by friction against the lip.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present invention may be derived byreferring to the detailed description and claims when considered inconnection with the Figures, wherein like reference numbers refer tosimilar items throughout the Figures, and:

FIG. 1 shows a back perspective view of a sheet feeder apparatus;

FIG. 2 shows a partial front perspective view of the sheet feederapparatus that includes a feeder mechanism in accordance with anembodiment;

FIG. 3 shows an enlarged partial front perspective view for the feedermechanism;

FIG. 4 shows a perspective view of a support bar for the feedermechanism;

FIG. 5 shows a side view of a pickup head for the feeder mechanism;

FIG. 6 shows a side view of a bracket component of an adjuster for thefeeder mechanism;

FIG. 7 shows a side view of a pivot arm component of the adjuster;

FIG. 8 shows a side view of a fastener component of an adjustmentmechanism for the adjuster;

FIG. 9 shows a side view of the pickup head and the adjuster mounted onthe support bar of the feeder mechanism in which the pickup head isoriented in a vertical position;

FIG. 10 shows a side view of the pickup head and adjuster mounted on thesupport bar of the feeder mechanism in which the pickup head is tiltedin a sheet transport direction; and

FIG. 11 shows a side view of the pickup head and adjuster mounted on thesupport bar of the feeder mechanism in which the pickup head is tiltedin a direction that is opposite to the sheet transport direction.

DETAILED DESCRIPTION

Sheet feeder apparatuses are used to pick up a variety of materialshaving different thicknesses, stiffness, sheet sizes, material qualityand so forth. In some instances, it may be necessary to adjust positionsof the pickup heads of a feeder mechanism for particular workingconditions and/or types of material. With particular regard to stiffpaper, such as cardstock, a typical stack of sheets may be curvedupwardly or downwardly at its leading edge. As such, when the suctioncups of vertically oriented pickup heads of a feeder mechanism arelowered to this curved surface, incomplete contact between the suctioncups and the stack of curved sheets can occur causing an air leakbetween the lip of the suction cup and the topmost sheet. Accordingly,sufficient suction may not be formed and the sheet material may not beeffectively held by friction against the lip of the suction cup. If thesheet material is not effectively held by the suction cups, feed-failurejams, overlapped feeding, and/or a number of other problems can occur.The term “feed-failure jam” refers to a condition in which a sheet ofmaterial is not well fed but stopped on the feeding path, which can leadto further complications. The term “overlapped feeding” refers to thecondition in which more than one sheet is fed together, with a part ofone sheet overlapped by a part of another sheet.

Embodiments disclosed herein entail a feeder mechanism in a sheet feederapparatus for picking up sheets of a material from a stack of sheets.The feeder mechanism includes suction pickup heads that can becollectively adjusted, or tilted, in a sheet transport direction toaccommodate curvature in the stack of sheets. Additionally, the suctionpickup heads can be individually adjusted in a lateral directionperpendicular to the sheet transport direction to accommodate varyingwidths of the sheet material. The various adjustments can be readilyaccomplished on the fly in accordance with changing materials andconditions. Moreover, the feeder mechanism may be implemented on avariety of sheet feeder apparatuses without undue modification to theapparatuses.

FIG. 1 shows a back perspective view of a sheet feeder apparatus 20.Sheet feeder apparatus 20 may be used to individually supply sheets of amaterial from a stack of sheets 22 to a downstream machine (not shown)such as a printer, printing press, or similar device. For clarity, thetopmost sheet from stack of sheets 22 is referred to herein as sheet 24.Accordingly, sheet 24 is picked up by a feeder mechanism (discussedbelow) and is transported in a sheet transport direction 26 onto atransport table 27 leading to the downstream machine.

Referring to FIGS. 2 and 3, FIG. 2 shows a partial front perspectiveview of sheet feeder apparatus 20 that includes a feeder mechanism 28 inaccordance with an embodiment, and FIG. 3 shows an enlarged partialfront perspective view of feeder mechanism 28. Feeder mechanism 28 isgenerally configured to pick up the topmost sheet 24 from stack ofsheets 22 (FIG. 1). Feeder mechanism 20 includes a support bar 30.Feeder mechanism 20 further includes one or more pickup heads 32suspended below support bar 30, and an adjuster 34 coupled to supportbar 30.

Feeder mechanism 28 is shown and described herein as being coupled withsheet feeder apparatus 20 for illustrative purposes. However, theelements of feeder mechanism 28 such as support bar 30, pickup heads 32,and adjuster 34 may be readily adapted for incorporation into othersheet feeder designs.

In an illustrative example, sheet feeder apparatus 20 may include twosets of control arms 36, each of which are located at opposing ends ofpivot and forward control shafts 38 and 40, respectively. Each set ofcontrol arms 36 can include a first control arm 42 and a second controlarm 44. Opposing ends of support bar 30 are constrained by, i.e., heldby, first control arm 42. In general, pivot and forward control shafts38 and 40, along with first and second control arms 42 and 44, functioncooperatively to drive feeder mechanism 28 upwardly and downwardly, aswell as forward and backward. That is, the opposing ends of support bar30 reside in a frame cutout 46 (shown in FIG. 3) of sheet feederapparatus 20, and a bearing (not shown) residing in frame cutout 46allows constrained relative motion of support bar 30 in an up/downdirection, represented by an arrow 48 in FIG. 3, and in aforward/backward direction, represented by an arrow 50 in FIG. 3. Thisconstrained relative motion causes pickup heads 32 to be driven intocontact with each successive sheet 24 in stack of sheets 22 (FIG. 1).

Support bar 30 is configured to pivotally couple to first control arms42 of sheet feeder apparatus 20. In an example, the ends of support bar30 are directed through apertures (not visible) in each of first controlarms 42 and connect to drive elements (not shown) of sheet feederapparatus 20 in a known manner. Accordingly, a longitudinal axis 52 ofsupport bar 30 is arranged substantially perpendicular to sheettransport direction 26 of sheet feeder apparatus 20. As will bediscussed in much greater detail below, support bar 30 can pivot aboutits longitudinal axis 52, where the degree of pivoting is controlled byadjuster 34. The pivot motion is represented by a curved, bi-directionalarrow 54 in FIGS. 2 and 3. Pivot motion 54 of support arm 30 causespickup heads 32 coupled to support arm 30 to tilt in a plane extendingsubstantially vertically (i.e., up/down) and in sheet transportdirection 26.

The materials to be fed by sheet feeder apparatus 20 can come in variouswidths. Accordingly, pickup heads 32 may also be suitably adjusted inaccordance with a width dimension 56 of sheet 24 in order to accommodatevarious widths of sheet 24. That is, pickup heads 32 are additionallylengthwise displaceable along support bar 30, where this lengthwisemotion is represented by a straight bi-directional arrow 58, as will bediscussed in greater detail below.

Referring to FIG. 4 in connection with FIG. 3, FIG. 4 shows aperspective view of support bar 30 of feeder mechanism 28. Support bar30 includes a first end 60, a second end 62, and an intermediate portion64 extending between first and second ends 60 and 62, respectively. Atleast one, and in this example, both of first and second ends 60 and 62is cylindrical in shape. In contrast, intermediate portion 64 has agenerally rectangular, and more specifically square, cross-section.

In some embodiments, the cylindrical first and second ends 60 and 62 maybe threaded onto or otherwise attached to the rectangular intermediateportion 64. However, in other embodiments, the cylindrical first andsecond ends 60 and 62 may be formed from a contiguous piece of machinedmetal. Intermediate portion 64 is illustrated as being discontinuous sothat first and second cylindrical ends 60 and 62 and the rectangularcross-section of intermediate portion 64 can be readily visualized. Itshould be readily apparent, however, that support bar 30 does notinclude a discontinuous region, as shown in FIG. 2.

Referring to FIG. 5 in connection with FIG. 3, FIG. 5 shows a side viewof one of pickup heads 32 of feeder mechanism 28. Although only onepickup head 32 is described in detail, it should be understood that thefollowing discussion applies equally to each of pickup heads 32 coupledto support bar 30 of feeder mechanism 28. Pickup head 32 includes ablock element 66, a suction tube 68 extending through block element 66,and a resilient suction cup 70 coupled to a distal end of suction tube68. In an embodiment, suction tube 68 may be able to move or slidewithin block element 66. Accordingly, pickup head 32 may further includea spring 72 residing on suction tube 68 between block element 66 andsuction cup 70. Spring 72 urges suction cup 70 away from block element66, but compresses as needed when suction cup 70 is driven into contactwith sheet 24 (FIG. 2).

Suction tube 68 is coupled to a vacuum hose 74, which in turn goes to aconventional suction source (not shown). Accordingly, a hollow space 76(shown in dashed line form in FIG. 5) circumscribed by the outerperimeter, i.e., a lip 78, of suction cup 70 is thus coupled to thesuction source. Vacuum hose 74 may be flexible to allow for the motionof feeder mechanism 28 relative to sheet feeder apparatus 20. Generallyvacuum is applied via the suction source when pickup heads 32 of feedermechanism 28 are driven in contact with the topmost sheet 24 in stack ofsheets 22 (FIG. 1). The vacuum is released when feeder mechanism 28 hasmoved sheet 24 onto transport table 27 (FIG. 1).

A passage 80 extends through block element 66. Passage 80 is generallyrectangular so as to match the generally rectangular cross-sectionalshape of intermediate portion 64 of support bar 30. In addition, passage80 is slightly larger than the cross-sectional dimensions ofintermediate portion 64 so that block element 66 can slide relativelyfreely lengthwise along intermediate portion 64. However, passage 80 issmall enough so that block element 66 cannot rotate about intermediateportion 64.

Pickup head 32 further includes a fastener element 82 having a shank 84in threaded engagement with block element 66. Shank 84 is configured toextend at least slightly into passage 80. Fastener element 82 furtherincludes a knob 86 coupled to shank 84. In operation, a user can turnfastener element 82 to move shank 84 out of passage 80 so that blockelement 66 can be slid along intermediate portion 64 of support bar 30to a desired position. Once pickup head 32 is appropriately located, theuser can turn fastener element 82 using knob 86 to move shank 84 intoabutment with intermediate portion 64 so that pickup head 32 is securedin place. Accordingly, each of pickup heads 32 can be individuallylengthwise displaced along intermediate portion 64 and then secured innon-pivotable engagement with support bar 30.

Referring now to FIGS. 6-8 in connection with FIG. 3, FIG. 6 shows aside view of a bracket component 88 of adjuster 34 for feeder mechanism28, FIG. 7 shows a side view of a pivot arm component 90 of adjuster 34,and FIG. 8 shows a side view of a fastener component 92 of an adjustmentmechanism for adjuster 34. In general, bracket 88, pivot arm 90, andfastener 92 are operably coupled to support bar 30 and function to pivotsupport bar 30 and, consequently, to tilt pickup heads 32 that aresecured to support bar 30.

With particular reference to FIGS. 3 and 6, bracket 88 is fixedlycoupled to intermediate portion 64 of support bar 30. To that end, apassage 94 extends through bracket 88. Passage 94 is generallyrectangular so as to match the generally rectangular cross-sectionalshape of intermediate portion 64 of support bar 30. In addition, passage94 is small enough so that bracket 88 cannot rotate about intermediateportion 64. In one exemplary configuration, passage 94 may be sized suchthat intermediate portion 64 is press fit into passage 94 to fix bracket88 to intermediate portion 64 of support bar 30. In another exemplaryconfiguration, bracket 88 may have a gap 96 extending between an outeredge of bracket 88 and passage 94. Gap 96 allows for slight displacementof opposing edges 98, 100 of bracket 88 at gap 96 so that intermediateportion 64 can be slid into passage 94. Once bracket 88 is suitablypositioned on intermediate portion 64, a threaded fastener (not shown)may be screwed into a corresponding threaded passage in bracket 88(represented by dashed lines) so as to close gap 96 and thereby fixbracket 88 to intermediate portion 64 of support bar 30. Those skilledin the art will recognize that alternative designs may be implementedfor fixedly coupling bracket 88 to the rectangular shaped intermediateportion 64.

With particular reference to FIGS. 3 and 7, pivot arm 90 is coupled tothe cylindrical first end 60 (FIG. 4) of support bar 30. To that end, apassage 102 extends through bracket pivot arm 90. Passage 102 isgenerally circular so as to match the generally circular cross-sectionalshape of first end 60 of support bar 30. In addition, passage 102 isslightly larger than the diameter of first end 60 so that support arm 30can pivot inside of and relative to passage 102.

Now with particular reference to FIGS. 3 and 8, an adjustment mechanism104 of adjuster 34 is coupled between bracket 88 and pivot arm 90.Adjustment mechanism 104 includes a post 106 (visible in FIG. 3) andfastener 92. Adjustment mechanism 104 is adapted to cause support bar 30to pivot, or rotate, relative to pivot arm 90 and thereby tilt pickupheads 32. Post 106 is in fixed engagement with pivot arm 90. Forexample, post 106 may be a separate component that is attached to pivotarm 90 via a threaded fastener 108, the head of which is visible in FIG.7. Alternatively, pivot arm 90 and post 106 may be machined as a singleintegral component. As most clearly seen in FIG. 3, post 106 isdisplaced away from and aligned substantially parallel to support bar30.

Fastener 92 is engaged with each of bracket 88 and post 106, and isoriented substantially perpendicular to support bar 30. In anembodiment, fastener 92 includes a threaded shank 110 attached to anadjustment knob 112. At least one of bracket 88 and post 106 includes acorresponding threaded opening. For example, post 106 includes athreaded opening 114 (see FIG. 3). Fastener 92 is directed through apassage 116 (see FIG. 3) in bracket 88, and is threaded into threadedopening 114. A spring element 118 resides on threaded shank 110 offastener 92 and is interposed between bracket 88 and post 106.

In operation, manual rotation of fastener 92 in a first direction, e.g.,clockwise, via adjustment knob 112 draws bracket 88 toward post 106.Movement of bracket 88 toward post 106 causes the corresponding rotationof support arm 30 relative to pivot arm 90 due to the fixed engagementof bracket 88 with support arm 30. As support arm 30 pivots, all ofpickup heads 32 coupled to support arm 30 will concurrently tilt in apredetermined direction. Similarly, manual rotation of fastener 92 in adirection opposite, e.g., counterclockwise, to the first direction viaadjustment knob 112 urges bracket 88 away from post 106. Movement ofbracket 88 away from post 106 causes corresponding rotation of supportarm 30 relative to pivot arm 90, and the subsequent tilting of pickupheads 32 in the opposite direction. Spring element 118 urges bracket 88away from post 106. However, spring element 118 compresses as neededwhen fastener 92 is manually rotated.

FIG. 9 shows a side view of one of pickup heads 32 and adjuster 34mounted on support bar 30 of feeder mechanism 28. In this exemplaryillustration, pickup head 32 is not tilted, but rather, is oriented in avertical position. Although the function of only one pickup head 32 isdescribed in connection with FIGS. 9 through 11 below, it should bereadily understood that that the ensuing descriptions apply equally toall pickup heads 32 of feeder mechanism 28.

As shown, stack of sheets 22 underlying suction cup 70 is generallyflat, i.e., not curved. As such, pickup head 32 is suitably positionedvertically so that as pickup head 32 is moved in downwardly inaccordance with up/down motion 48 of control arms 36 (FIG. 3), suctioncup 70 of pickup head 32 is driven into contact with each successivesheet 24 in stack of sheets 22. In this scenario in which stack ofsheets 22 is substantially flat, the vertical orientation of pickup head32 enables generally complete contact between suction cup 70 and thetopmost sheet 24. Thus, an air leak between suction cup 70 and sheet 24is less likely to occur so that sufficient suction can be formed to holdsheet 24 against lip 78 of suction cup 70 while sheet 24 is being movedin sheet transport direction 26.

FIG. 10 shows a side view of one of pickup heads 32 and adjuster 34mounted on support bar 30 of feeder mechanism 28. In this exemplaryillustration, pickup head 32 is tilted in sheet transport direction 26.As shown, a leading edge of stack of sheets 22 underlying suction cup 70of pickup head 32 is generally upwardly curved. This curvature can beespecially prevalent when stack of sheets 22 is of relatively stiffstock material. Thus, pickup head 32 is currently tilted away from thevertical orientation at a tilt angle 120 in sheet transport direction 26to align with the curvature in stack of sheets 22. In order to do so,adjustment knob 112 is turned in a clockwise direction 122 to rotatethreaded fastener 92. Adjustment knob 112 may be readily manually turnedby an operator of sheet feeder apparatus 20 (FIG. 1) in order toaccommodate the curvature of a stack of sheets 22.

Rotation of fastener 92 in clockwise direction 122 draws bracket 88toward post 106 (FIG. 3) coupled to pivot arm 90. As bracket 88 is drawntoward post 106, support bar 30 rotates in passage 102 extending throughpivot arm 90 due to the fixed coupling of bracket 88 to intermediateportion 64 (FIG. 4) of support bar 30. Pickup head 32 tilts in sheettransport direction 26 corresponding with the rotation of support bar30. That is, bracket 88, support bar 30, and pickup head 32 are jointlymovable in contrast to a generally non-movable pivot arm 90.

Pickup head 32 is tilted to suitably align with the curvature of stackof sheets 22. Accordingly, as pickup head 32 is moved downwardly inaccordance with up/down motion 48 of control arms 36 (FIG. 3), suctioncup 70 of pickup head 32 is driven into contact with each successivesheet 24 in stack of sheets 22. In this scenario in which the leadingedge of stack of sheets 22 is upwardly curved, tilt angle 120 of pickuphead 32 in sheet transport direction 26 enables generally completecontact between suction cup 70 and the topmost sheet 24. Thus, an airleak between suction cup 70 and sheet 24 is less likely to occur so thatsufficient suction can be formed to hold sheet 24 against lip 78 ofsuction cup 70 while sheet 24 is being moved in sheet transportdirection 26.

FIG. 11 shows a side view of one of pickup heads 32 and adjuster 34mounted on support bar 30 of feeder mechanism 28. In this exemplaryillustration, pickup head 32 is tilted in a direction opposite to sheettransport direction 26. As shown, a leading edge of stack of sheets 22underlying suction cup 70 of pickup head 32 is generally downwardlycurved. Thus, pickup head 32 is currently tilted away from the verticalorientation at a tilt angle 124 in a direction opposite from sheettransport direction 26 so as to align with the downward curvature instack of sheets 22. In order to do so, adjustment knob 112 is manuallyturned in a counterclockwise direction 126 to rotate threaded fastener92 in order to accommodate the curvature of a stack of sheets 22.

Rotation of fastener 92 in counterclockwise direction 126 urges bracket88 away from post 106 (FIG. 3) coupled to pivot arm 90. As bracket 88 isurged away from post 106, support bar 30 rotates in passage 102extending through pivot arm 90 due to the fixed coupling of bracket 88to intermediate portion 64 (FIG. 4) of support bar 30. Pickup head 32tilts opposite to sheet transport direction 26 corresponding with therotation of support bar 30 to best align with the curvature of stack ofsheets 22.

Accordingly, as pickup head 32 is moved downwardly in accordance withup/down motion 48 of control arms 36 (FIG. 3), suction cup 70 of pickuphead 32 is driven into contact with each successive sheet 24 in stack ofsheets 22. In this scenario in which the leading edge of stack of sheets22 is downwardly curved, tilt angle 124 of pickup head 32 opposite fromsheet transport direction 26 enables generally complete contact betweensuction cup 70 and the topmost sheet 24. Thus, an air leak betweensuction cup 70 and sheet 24 is less likely to occur so that sufficientsuction can be formed to hold sheet 24 against lip 78 of suction cup 70while sheet 24 is being moved in sheet transport direction 26.

In summary, embodiments of the invention entail a feeder mechanism in asheet feeder apparatus for picking up sheets of a material from a stackof sheets. The feeder mechanism includes suction pickup heads that canbe collectively adjusted, or tilted, forwardly or backwardly in a planeparallel to a sheet transport direction of the sheet feeder apparatus inorder to accommodate curvature in the stack of sheets. Additionally, thesuction pickup heads can be individually adjusted in a lateral directionperpendicular to the sheet transport direction to accommodate varyingwidths of the sheet material. The various adjustments can be manuallyaccomplished by an operator on the fly in accordance with changingmaterials and conditions. Moreover, the feeder mechanism may beimplemented on a variety of sheet feeder apparatuses without unduemodification to the apparatuses.

Although the preferred embodiments of the invention have beenillustrated and described in detail, it will be readily apparent tothose skilled in the art that various modifications may be made thereinwithout departing from the spirit of the invention or from the scope ofthe appended claims. That is, it should be appreciated that theexemplary embodiments are only examples, and are not intended to limitthe scope, applicability, or configuration of the invention.

1. In a sheet feeder apparatus, a feeder mechanism for picking up sheetsfrom a stack of sheets comprising: a support bar configured to pivotallycouple to control arms of said sheet feeder apparatus, said support barincluding a first end, a second end, and an intermediate portion betweensaid first and second ends, at least one of said first and second endsbeing a cylindrical end; a pickup head coupled to said support bar atsaid intermediate portion; and an adjuster coupled to said support barat said cylindrical end, said adjuster being configured to pivot saidsupport bar to tilt said pickup head; wherein said adjuster comprises: abracket fixedly coupled to said intermediate portion of said supportbar; a pivot arm coupled to said cylindrical end of said support bar,said pivot arm being selectively pivotable about said cylindrical end ofsaid support bar; and an adjustment mechanism coupled between saidbracket and said pivot arm and adapted to pivot said support barrelative to said pivot arm and thereby tilt said pickup head, saidadjustment mechanism including a post and a fastener, said post being infixed engagement with said pivot arm, said post being displaced awayfrom and aligned substantially parallel to said support bar, saidfastener being engaged with each of said bracket and said post, and saidfastener being oriented substantially perpendicular to said support bar,wherein one of said bracket and said post includes a threaded opening,said fastener is a threaded fastener that extends through said threadedopening, and rotation of said threaded fastener in a first directiondraws said bracket toward said post to cause said pickup head to tilt ina sheet transport direction of said sheet feeder apparatus, and rotationof said threaded fastener in a direction opposite to said firstdirection urges said bracket away from said post to cause said pickuphead to tilt in a direction opposite to said sheet transport direction.2. A feeder mechanism as claimed in claim 1 wherein: a longitudinal axisof said support bar is arranged perpendicular to a sheet transportdirection of said sheet feeder apparatus; said pickup head is suspendedbelow said support bar and configured to be driven into contact withsuccessive ones of said sheets; and said adjuster pivots said supportbar about said longitudinal axis to selectively tilt said pickup head ina plane extending substantially vertically and in said sheet transportdirection. 3-5. (canceled)
 6. A feeder mechanism as claimed in claim 1wherein said threaded fastener includes an adjustment knob for manualrotation of said threaded fastener.
 7. In a sheet feeder apparatus, afeeder mechanism for picking up sheets from a stack of sheetscomprising: a support bar configured to pivotally couple to control armsof said sheet feeder apparatus, said support bar including a first end,a second end, and an intermediate portion between said first and secondends, at least one of said first and second ends being a cylindricalend; a pickup head coupled to said support bar at said intermediateportion; and an adjuster coupled to said support bar at said cylindricalend, said adjuster being configured to pivot said support bar to tiltsaid pickup head wherein said adjuster comprises: a bracket fixedlycoupled to said intermediate portion of said support bar; a pivot armcoupled to said cylindrical end of said support bar, said pivot armbeing selectively pivotable about said cylindrical end of said supportbar; and an adjustment mechanism coupled between said bracket and saidpivot arm and adapted to pivot said support bar relative to said pivotarm and thereby tilt said pickup head, wherein said adjustment mechanismincludes a post, a fastener, and a spring element, said post being infixed engagement with said pivot arm, said post being displaced awayfrom and aligned substantially parallel to said support bar, saidfastener being engaged with each of said bracket and said post, saidfastener being oriented substantially perpendicular to said support bar,and said spring element residing on said fastener and interposed betweensaid bracket and said post.
 8. A feeder mechanism as claimed in claim 1further comprising multiple pickup heads coupled to said support bar atsaid intermediate portion, said pickup head being one of said multiplepickup heads, wherein pivoting said support bar concurrently tilts eachof said pickup heads.
 9. A feeder mechanism as claimed in claim 1wherein said pickup head is in non-pivotable engagement with saidsupport bar.
 10. A feeder mechanism as claimed in claim 1 wherein saidintermediate portion of said support bar has a generally rectangularcross section.
 11. A feeder mechanism as claimed in claim 1 wherein saidpickup head is lengthwise displaceable along said support bar.
 12. Afeeder mechanism as claimed in claim 1 further comprising multiplepickup heads coupled to said support bar at said intermediate portion,said pickup head being one of said multiple pickup heads, and each ofsaid multiple pickup heads being individually lengthwise displaceablealong said support bar. 13-18. (canceled)
 19. In a sheet feederapparatus, a feeder mechanism for picking up sheets from a stack ofsheets comprising: a support bar configured to pivotally couple tocontrol arms of said sheet feeder apparatus, said support bar includinga first end, a second end, and an intermediate portion between saidfirst and second ends, at least one of said first and second ends beinga cylindrical end; multiple pickup heads coupled to said support bar atsaid intermediate portion; and an adjuster coupled to said support barat said cylindrical end, said adjuster being configured to pivot saidsupport bar to concurrently tilt each of said pickup heads, saidadjuster including: a bracket fixedly coupled to said intermediateportion of said support bar; a pivot arm coupled to said cylindrical endof said support bar, said pivot arm being selectively pivotable aboutsaid cylindrical end of said support bar; and an adjustment mechanismcoupled between said bracket and said pivot arm and adapted to pivotsaid support bar relative to said pivot arm and thereby tilt said eachof said pickup heads, said adjustment mechanism including a post and afastener, said post being in fixed engagement with said pivot arm, saidpost being displaced away from and aligned substantially parallel tosaid support bar, said fastener being engaged with each of said bracketand said post, and said fastener being oriented substantiallyperpendicular said support bar; wherein one of said bracket and saidpost includes a threaded opening, said fastener is a threaded fastenerthat extends through said threaded opening, and rotation of saidthreaded fastener in a first direction draws said bracket toward saidpost to cause said each of said pickup heads to tilt in a sheettransport direction of said sheet feeder apparatus, and rotation of saidthreaded fastener in a direction opposite to said first direction urgessaid bracket away from said post to cause said pickup head to tilt in adirection opposite to said sheet transport direction.
 20. (canceled)